Epithelial tissue Flashcards
CHARACTERISTICS AND EMBRYONIC ORIGIN OF
EPITHELIAL TISSUE
clue: CAED
CHARACTERISED BY HIGH CELLULARITY
* AVASCULAR
* EXHIBIT POLARITY
* DERIVED FROM EMBRYONIC GERM LAYERS
EPITHELIA THE COVERS THE EXTERNAL SURFACES
(outside the body)
clue: also starts with the letter E
Ectoderm
EPITHELIA OF THE HEART, BLOOD, LYMPH VESSELS, SEROUS CAVITIES, URINARY SYSTEM, MALE AND
FEMALE REPRODUCTIVE SYSTEMS
clue: BLUSH FM -
b- blood
l- lymph
u- urinary system
s- serous cavities
h- heart
female- female reproductive systems
m- male
Mesoderm
EPITHELIA THE OF THE DIGESTIVE TRACT, LIVER, PANCREAS, RESPIRATORY TRACT, URINARY BLADDER,
URETHRA
clue: everything here is inside the body
ENDO means inside
ENDODERM
AMORPHOUS EXTRACELLULAR MATERIAL
* MIXTURE OF DIFFERENT KINDS OF GLYCOPROTEINS, COLLAGENS, AND
PROTEOGLYCANS
* 20-100nm THICK
* PRODUCED BY THE EPITHELIAL CELLS
BASAL LAMINA
LAYER OF EXTRACELLULAR MATERIAL BETWEEN BASAL LAMINA AND THE
UNDERLYING TISSUE.
* THICKER THAN THE BASAL LAMINA
* 200-500nm THICK
* PRODUCED BY FIBROBLASTS THAT FORM THE CONNECTIVE TISSUES
LAMINA FIBRORETICULARIS
BASAL LAMINA AND LAMINA FIBRORETICULARIS ARE COLLECTIVELY CALLED
BASEMENT MEMBRANE
SINGLE LAYER OF FLATTENED CELLS
* NUCLEUS OCCUPIES THE THICKEST PART OF THE CELLS
* THE SURFACE EXHIBITS IRREGULAR POLYGONAL OUTLINES
* LINES THE LUNG ALVEOLI, BOWMAN’S CAPSULE
clue : flat- squamous
SIMPLE SQUAMOUS EPITHELIUM
EPITHELIUM THAT LINES THE SEROUS CAVITIES
(PERICARDIUM, PERITONIUM, PLEURA)
MESOTHELIUM-
EPITHELIUM THAT LINES THE LUMINAR SURFACE OF THE HEART, BLOOD, AND LYMPH VESSELS
ENDOTHELIUM-
SINGLE LAYER OF CELLS WHOSE HEIGHT APPROXIMATES THEIR
WIDTH (SQUARE)
* NUCLEI ARE ROUND AND CENTERED
* THE TOP VIEW SHOWS A POLYHEDRAL OUTLINE
* LINES CERTAIN PARTS OF THE SALIVARY GLAND DUCTS,
PANCREAS, TUBULES OF THE KIDNEY, ETC.
SIMPLE CUBOIDAL EPITHELIUM
SINGLE LAYER OF TALL CELLS
* NUCLEI OF THE CELLS FORM ROWS
* OVAL, MORE BASAL THAN APICAL IN LOCATION
* LONG AXES LIE PARALLEL
* LINES THE STOMACH, INTESTINES AND LARGE DUCTS OF SOME EXOCRINE
GLANDS
Clue: tal like columns
SIMPLE COLUMNAR EPITHELIUM
VARIANT OF SIMPLE COLUMNAR EPITHELIUM
MEANS “FALSE STRATIFIED EPITHELIUM”
CONSISTS OF A SINGLE LAYER OF COLUMNAR OR CUBOIDAL EPITHELIUM
CELLS VARY IN SHAPE, NUCLEI ARE LOCATED IN VARIOUS LEVELS
CELLS CONSTITUTE ONLY ONE LAYER. ALL ARE ATTACHED ON THE BASAL
LAMINA
PSEUDOSTRATIFIED COLUMNAR EPITHELIUM
- LINES THE AIRWAYS OF THE RESPIRATORY SYSTEM
- this is also called ___
- CILIATED PSEUDOSTRATIFIED COLUMNAR EPITHELIUM
- RESPIRATORY EPITHELIUM
SHAPE IS FURTHER CLASSIFIED BASED ON THE CELLS IN THEIR
MOST SUPERFICIAL LAYER
- CELLS IN THE MOST SUPERFICIAL LAYER ARE FLAT OR PLAQUE-LIKE, DEEPER LAYERS
ARE CUBOIDAL OR COLUMNAR. - NEW CELLS ARE FORMED IN THE _____ . THE CELLS ON ____ ARE “OLD CELLS”
PUSHED TO THE SURFACE BY THE NEWLY FORMED ONES.
most superficial layer- flat
STRATIFIED SQUAMOUS EPITHELIUM
bottom, top
- DRY” EPITHELIUM
* DEAD CELLS
* HAVE NO NUCLEUS AND ORGANELLES
* WATER-RESISTANT - FORMS THE OUTER LAYER OF THE SKIN REFERRED TO AS __
- – KERATINIZED STRATIFIED SQUAMOUS EPITHELIUM
- EPIDERMIS
WET” EPITHELIUM
KEPT MOIST BY THE GLANDULAR SECRETIONS
CELLS IN THE MOST SUPERFICIAL ARE FLATTENED BUT STILL HAVE A
NUCLEUS
LINES THE ORAL CAVITY, ESOPHAGUS, VAGINA, URETHRA, MOST
SUPERFICIAL LATER OF THE CORNEA.
NONKERATINIZED STRATIFIED SQUAMOUS
EPITHELIUM
CONSIST OF 2 OR 3 LAYERS OF CUBOIDAL CELLS
* LINES THE MEDIUM-SIZED DUCTS OF SALIVARY GLANDS
STRATIFIED CUBOIDAL EPITHELIUM
CONSIST OF AT LEAST 2 LAYERS OF COLUMNAR CELLS. CELLS OF THE DEEPER
LAYER ARE CUBOIDAL.
* LINES LARGE DUCTS OF DOME ORGANS
STRATIFIED COLUMNAR EPITHELIUM
TYPE OF STRATIFIED EPITHELIUM UNIQUE TO MAMMALS
* CHARACTERISTICS ARE IN BETWEEN STRATIFIED SQUAMOUS AND STRATIFIED CUBOIDAL EPITHELIA.
* LINES THE URINARY PASSAGES AND THE URINARY BLADDER
* CAN WITHSTAND STRETCHING
ALSO REFERRED TO AS UROTHELIUM
TRANSITIONAL EPITHELIUM
SUPERFICIAL CELLS of transitional epithelium is called _____ BULGE
OUT INTO THE LUMEN GIVING THE CELLS A DOME-SHAPE PROFILE
“UMBRELLA CELLS”
SUPERFICIAL CELLS GET STRETCHED AND FLATTEN OUT- TRANSFORMING THE
EPITHELIUM INTO
STRATIFIED SQUAMOUS.
FINGER-LIKE EXTENSIONS OR PROCESSES OF THE PLASMA MEMBRANE
* FORM A FUZZY FINE VERTICAL LINE ON THE SURFACE OF THE EPITHELIUM
CALLED STRIATED BORDER/ BRUSH BRODER.
* COATED BY THE GLYCOCALYX
* THE CORE IS FORMED BY ACTIN FILAMENTS
THE MAIN FUNCTION IS TO INCREASE THE SURFACE AREA OF THE
EPITHELIUM
clue: fuzzy fine vertical line also called striated boarder or brush border -
SB - M
Starbucks - Mahal : ((
MICROVILLI
PRESENT IN THE SURFACES OF CELLS SPECIALIZED FOR THE
TRANSPORT OF FLUID OR MUCUS OVER THE SURFACE OF THE
EPITHELIUM
- ALSO FINGER-LIKE EXTENSIONS
- LONGER AND THICKER THAN MICROVILLI
- AXONEME (CORE) ARE CONSIST OF MICROTUBULES
- THEY ARE MOTILE.
CLUE: longer and thicker than microvilli
LTM - C
CILIA (KINOCILIA)
LIKE CILIA BUT LONGER
* SPERMATOZOON IS THE ONLY HUMAN CELL THAT HAS
FLAGELLUM (TAIL)
* MAIN FUNCTION IS TO PROPEL THE CELL ALONG THE FEMALE
GENITAL TRACT
clue: like cilia but longer- F
LC BL - F
FLAGELLA
LIKE MICROVILLI BUT ARE AS LONG AS CILIA
LIKE MICROVILLI- NONMOTILE, AND THEIR CORES CONSIST OF ACTIN FILAMENT
clue: Like microvili but as long as cilia
LMBC- S
STEREOCILIA
MOST APICALLY SITUATED OF THE JUNCTION COMPLEXES.
* LOCATED ON THE LATERAL SURFACE OF EACH CELL BELOW THE FREE SURFACE
OF THE CELL.
* ALLOWS CELL MEMBRANES TO STICK TOGETHER (W/OUT INTERVENING
INTERCELLULAR SUBSTANCES)
ZONULA OCCLUDENS
LOCATED BELOW THE ZONULA OCCLUDENS
* FORM BANDS COMPLETELY ENCIRCLE THE CELL
* CELL MEMBRANES ARE VERY CLOSE TO EACH OTHER (NEITHER ADHERE NOR
FUSE) AND SEPARATED BY NARROW INTERCELLULAR SPACE THAT BINDS CELL
MEMBRANE
ZONULA ADHERENS (ADHERENS JUNCTION; ADHERING
BELT; BELT DESMOSOME; BAND DESMOSOME)
LOCATED BELOW THE ZONULA ADHERENS.
* FORM BUTTON-LIKE ADHESIONS ARRANGED IN A LINE AROUND THE CELL
* APPEAR AS THICKENINGS OF THE CELL MEMBRANE
* CONSIST OF AN OVOID PROTEIN DISC THAT SPLITS INTO HALVES.
* WITHIN THE 2 OPPOSING CELLS, KERATINE FILAMENTS CONVERGE AND
INSERT INTO EACH HALF-DIS
DESMOSOMES
GAP junction ALLOW CELLS TO EXCHANGE IONS AND SMALL MOLECULES THROUGH TINY
TUBES CALLED
Connexons
PRESENT IN THE STRATUM BASALE OF THE EPIDERMIS OF THE SKIN
HELP ANCHOR THE CELLS TO THE UNDERLYING BASAL LAMINA
HEMIDESMOSOME
PRESENT IN THE CELL LININGS ALONG RENAL TUBULE
INCREASES THE ABSORBING CAPACITY OF A CELL
BASAL INFOLDING OF PLASMALEMMA
SECRETIONS ARE RELEASED ONTO THE SURFACE
EPITHELIUM; TRANSPORTS SECRETIONS THROUGH DUCTS
Clue: Exo- with ducts
EXOCRINE GLANDS
SECRETIONS ARE RELEASED INTO THE BLOOD OR
LYMPH; DUCTLESS
Clue: Endo- without ducts (ductless)
ENDOCRINE GLANDS
CHEMICAL SUBSTANCES CARRIED BY THE
BLOOD TO THE TARGET CELLS/TISSUES THAT HAVE RECEPTORS.
ACTS
AS A CHEMICAL MESSENGER.
Hormones
ANY SURFACE EPITHELIUM, WHERE MOST OF THE CELLS ARE SECRETORY
EX
* EPENDYMA- LINES THE CHOROID PLEXUSES IN THE BRAIN. PRODUCES
CSF
SECRETORY EPITHELIAL SHEET
GROUP OF SECRETORY CELLS IN A SURFACE EPITHELIUM THAT GATHER
TOGETHER AROUND A SMALL ORIFICE THAT SERVES AS A DUCT
* FORMS A SHALLOW INVAGINATION WITHIN THE EPITHELIAL SURFACE
* EPITHELIUM THAT LINES THE PENILE URETHRA
INTRAEPITHELIAL GLAND
POSSESS TRUE DUCTS
* SECRETORY UNITS LIE UNDERNEATH THE EPITHELIUM
* SECRETIONS PASS THROUGH A TUBULAR STRUCTURE CALLED A
DUCT OR SYSTEM OF DUCTS
EXOCRINE GLANDS WITH DUCTS
PRODUCE VISCOUS SECRETIONS
THAT CONTAINS MUCIN THAT
WHEN HYDRATED BECOMES MUCUS THAT PROTECTS AND LUBRICATES THE
EPITHELIA; MUCOUS ALVEOL
Clue : Mucin - M
MUCOUS CELLS-
- PRODUCE THIN, WATERY SECRETIONS OFTEN CONTAIN EZYMES;
SEROUS ALVEOLI
SEROUS CELLS
SECRETIONS ARE RELEASED THROUGH EXOCYTOSIS;
SALIVARY GLAND AND PANCREAS
DOES NOT
RESULT IN THE LOSS OF ANY PART OF THE CELL;
MEROCRINE
; SEBACEOUS GLAND OF THE SKIN
RELEASE OF SECRETION ENTAILS DESTRUCTION OF CELLS
HOLOCRINE
; CERUMINOUS GLANDS OF THE EXTERNAL AUDITORY MEATUS
APICAL PART OF THE CELL IS RELEASED TOGETHER WITH THE
SECRETORY PRODUCT
clue: apical
APOCRINE
FLATTENED, STELLATE CELLS FOUND BETWEEN THE EPITHELIAL
CELL AND THE BASAL LAMINA.
* CONTAIN ACTIN
* THEY ARE CONTRACTILE
* PRESENT IN THE SWEAT GLANDS, MAMMARY GLANDS,
LACRIMAL GLANDS, SALIVARY GLANDS
CONTRACTION EJECTS THE SECRETIONS OF THE ACINI INTO THE
DUCTS
MYOEPITHELIAL CELLS (BASKET CELLS)
